Fuel pump for internal-combustion engines



March 16, 11948. G. E. SEALs 2,437,838

FUEL PUMP FOR INTERNAL;COMBUST-ION ENGINES Filed Dec. 24, 1942 2sheets-sheet 1 INVENT OR.

March 1e, 194s. G. E. SEALS 2,437,838

I TUEL PUMP FOR INTERNAL-COMBUSTION ENGINES Filed Dec. 24, 1942 2Sheets-Sheet 2 /a/vcfzy. j?

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Patented Mar. 16, 1948 UNITED STATES 2,437,&8

FUEL PUIWP FOR INTERNAL-COMBUSTION ENGINES Garlin E. Seals, San Antonio,Tex. Application December 24. f942rvSerial No. 470,047

Another object of the invention is to provide a l fuel controlarrangement including a multitoothed cam, rotated by a lever, and aplurality of roller followers equal in number to and reciprocated by theteeth of the cam and carried by the plungers of the fuel pump so thatvarying positions of the cam will determine the lengths of strokes ofthe pump plungers and consequently the quantity of fuel deliveredthereby into the cylinders.

Another object of the invention is to provide a rapid and highlyeffective scavenging and exhaust system for the cylinders, utilizing asan accelerating medium the air blast of the propeller blades, augmentedby a blower in a fresh air chamber serving each cylinder and throughwhich arrangement, a considerable reduction of back pressure from thecylinders is effected and more complete evacuation thereof obtainedwithout requiring a special pump for the purpose.

Still another object of the invention is to provide means embracing theintake ports of each cylinder for introducing fresh air under pressureat an angle upward and this, combined with a deecting device carried bythe piston head, very effectively drives out all stale charges throughthe exhaust ports of the cylinders.

- With the foregoing objects as paramount, the invention has particularreference to certain features of accomplishment, to become manifest asthe description proceeds, taken in connection with the accompanyingdrawings, wherein:

Figure 1 is a perspective view of an engine constructed according to thepresent invention.

Figure 2 is an elevational view in vertical section.

Figure 3 is a perspective view of the case containing the cam actuatingthe fuel injectors, with parts broken away.

Figure 4 is a perspective view of one of the fuel injectors partly invertical longitudinal section.

Figure 5 is a cross section of the crank shaft PATENT GFFICE (Cl. S-3,7)

showing the position of the fuel injector cam, also the fuel controlcam.

Figure 6 is a view similar to Figure 5 but-showing the fuel control camin position for greater/-V 5 fuel injection.

' Figure 7 is a horizontal cross section through the intake and exhaustports of a cylinder.

Figure 8 is a perspective View of the air intake, a continuation thereofshown in Figure 1, and

Figure 9 is a fragmentary detail view of a blower adapted to acceleratethe air intake of the cylinder.

Figure 10 is a view of one of the fuel injector pumps in longitudinalsection.

In conventional types of two cycle engines, the burnt gases areevacuated from the cylinder by the injection of the unburnt fuelmixture. On the compression stroke the piston draws in a fresh charge offuel from the crank case and when the piston is driven down bycombustion, the crank case charge is compressed until, near the end ofits stroke, the piston uncovers a port in the cylinder through which thefuel from the crank case is forced in. Just prior to this introductionof fuel, the piston uncovers an exhaust port in the opposite side of thecylinder and the burnt gases flow out before the fresh charge enters thecylinder and the incoming gas is directed upward to scavenge thecylinder. The objectionable fea.-

ture of this method of evacuating the cylinders `lies in the fact thatthe burnt gases are never completely scavenged and the fresh charge offuel is always more or less diluted by the product of combustionremaining from the' previous charge. This results in loss of power andfaulty ignition of the charge. Accordingly, it is the chief object ofthe present invention to correct the faults which have caused the twocycle engine to be heretofore regarded as unreliable and Vinefflcient.

Continuing with a more detailed description of the drawings, referenceis primarily made to Figures 1 and 2 wherein reference numeral 6 isemployed to generally denote the engine. As illustrated, the engine hasnine cylinders 'l which are air cooled through the provision of fins 8disposed radially thereon. Each cylinder 1 has a piston 9 reciprocablyarranged ltherein provided with a wrist pin I0 to which is connected aconnecting rod I I and through which power is transmitted to a crank i2,and to the crank shaft I3. The crank shaft is journaled in bearings' I4and is adapted to supply power to drive any character of machine' but inthe present case, the propeller 55 P of an airplane.

Exhaust ports I5 are provided in the cylinder 1, communicating with anexhaust manifold I8 and exhausting to atmosphere at I1 throughaccelerating tubes I8 (Fig. 7). The air through the tubes I8 is thatblown rearwardly by the propeller P and enters by way of the ared endsI9 of the tubes I8. This exhaust system is highly effective in reducingthe back pressure from the cylinder and thus more completely evacuatethe same.

For scavenging the cylinder and also for combustion, fresh air entersthrough the belled end 20 of the riser tube bearing the same characterof reference and which is covered by a dust screen 20a. The air flows inthe direction of the arrows, past the butterfly valve 2 I, through thechamber 22, which extends completely around the engine and with whichthe tube 2U communicates, serving as the common means of fresh airsupply.

In the chamber'22 there is provided a blower of the well known typesuggested in Figure 9 and which consists of interengaging lmpellers 22a,driven by enmeshed gears 22h, the latter in turn, being driven by alarge gear 22e, mounted rigidly upon the crank shaft I3. The fresh airdelivered by this blower enters passage 23 and inlet ports 24 to thecylinder 1.

Gasoline fuel enters feed pipe 25 from a fuel tank (not shown), throughinjector 26, flowing through check valves 21 and tube 28 to spray nozzle29, where it is atomized and thoroughly mixed with the incoming air. Aball check29a is provided in the tube 28 at the point where it entersthe spray head and is held under slight tension of a coiled spring toprevent back firing into the line when explosions occur in the cylinder1, At prearranged points in the' cycle, the electrical current passesthrough the wire 3I (Fig.

1) from the magneto, distributor 3Ia, timing gears 3Ib, through sparkplugs 30 and there creates a spark for ignition.

Reciprocably arranged in the pump cylinder 26 is a plunger 32. Thisplunger is actuated by a cam 33, shown in detail in Figures 3, 5 and 6,the cam being secured to rotate with the crank shaft 'I3 by means'of thekey 34. The cam 33 reciprocates the plunger 32 of the pump by reason ofits peripheral engagement with the roller followers 35, one beingmounted on the end of each reciprocating plunger rod 32a, and impartthereto an outward radial motion, the rod being returned by a coiledspring 36. There is, of course, one injector for each cylinder, alloperated by the same cam 33.

In order to control the supply of fuel to the cylinders. a toothed,circular cam 31 is provided, which is capable of rotation, this beingeffected by means of a control lever 38. In the-position of this cam, asshown in Figure 5, the roller followers 35 are on the tips of the teethof this adjustable cam and therefore cam 33 in rotating, will impartlbut slight motion to the injector plunger 32, hence injecting verylittle fuel, corresponding to an idling position. Figure 6 shows thisadjustable cam in a position in which the roller followers 35 run on thetips of the teeth of cam 31 but are under control of cam 33 andtherefore the reciprocating motion of the injector plunger is muchgreater than in the Figure 5 position. In this manner a greater quantityof fuel is injected per cycle. This corresponds to a fully openedthrottle accelerating position.

In Figure 3 is shown one fuel injector push rod 32 with spring 35 and aroller bearing on the cam 33. Figure 4 shows the manner in which thefuel from line 25 enters the pump cylinder 26 and upon actuating theplunger 32, it enters the ports a therein, lifting the lower valve 21,against `the resistance of its spring, to continue past the upper valve21 into the fuel line 28 to enter the cylinder. A fuel return line 36ais provided havlng a ball check 36h therein (Fig. 2) which extendsbetween the line 28, near its top and the fuel supply line 25. Thisreturn line is effective to pass fuel back into the supply line in eventof clogging of the spray nozzle 29 and possible rupture of the injectorline which would present a fire hazard. A screw adjustment 36c isprovided in return line 36a to control the tension of the valve spring.

The butterfly valve 2I shown in Flgure2 and which controls the airsupply through the tube 20 has a lever 38a which is connected by meansof a rod 38h, with the control lever 38 of the toothed cam 31 so thatthe positions of the butterfly valve, toothed cam 31 and control lever38 may be synchronously actuated from the cockpit by control rod 38C.

A conventional system of lubrication for the engine is provided. Thisconsists of an oil pump 39 which deliversoil through oil line 40 to theaxial passage 4I in the crank shaft I3. Ports 42 provide communicationbetween this passage and the crank shaft bearings and port 43 provideslubrication for the rod bearings. It is further pointed out that oilfrom the crank case iiows through pipe 44 to the reserve supply or pumpfrom which it returns to the oil pump 39 by way of the pipe 45. v

In operation; a cycle starts by air being forced into tube 20, throughdust screen 20a, past butterfiy valve 2|, to the chambers 22 of thefresh air manifold which its pressure is increased by blower 22a and isdelivered thereby through cylinder passage 23 andv into the cylinder 1through intake ports 24. The piston on its upward stroke closes ports 24and I5, the former first, due to the presence ofan elevation 24a on thehead of the piston, confronting the ports 24, and which providesadditional time for evacuation through ports I5. In thus moving, thecompression stroke is started. Fuel is tnen immediateiy forced into thecylinder through the line 28 and sprayed therein by the nozzle 29, asuilicient quantity of air being mixed with the atomized fuel throughcompression. It is important at this point to note that the -skirt ofthe piston is sufficiently long to keep the ports covered while at thetop, to prevent communication with the crank case.

When the piston has reached a predetermined point in` its down stroke, atimer passes the current through the spark plugs 30, causing theignition of the fuel mixture in the customary manner. ,The piston thenstarts on its downward' onpower stroke. the gases expanding until theexhaust ports I5 are uncovered whence the burnt gases proceed to flowthrough these ports and' the exhaust manifold I6 and discharge tovertical center line, which roller is raised about midway of the highesttooth of the star cam.

As the cam 33 turns with the crank shaft thevarious rollers, as shown,roll around the circular periphery until the cam depression 46 isreached, whence the -roller follows the depression until intercepted bythe toothed cam. The degree to which the roller moves inwardly orfollows this depression indicates the size of the fuel charge, thus aslight movement of the rollers would constitute a slight charge and alarge movement of the rollers inward would result in a heavy charge.

As this is a two stroke cycle, nine power strokes are produced eachrevolution instead of nine power strokes every two revolutions, as inthe conventional aviation engine. Moreover, the engine herein describedfurther differs from the conventional in that it incorporates theprinciples of both the Diesel and other types of gasoline engines, andalthough it embraces the two cycle principle, it does not receivelubricant or fuel through the crank case in the manner of most types oftwo cycle engines but rather, is fed in such a way that the fuel isnever mixed with oil nor the oil diluted by fuel. The lubricating systemis in no wise hindered by fuel induction.

It is further important to observe that by virtue of the flared tubesi9, which enter the exhaust manifold i6, it is possible in scavenging,to establish in the manifold I6 a partial vacuum which is effective toaid in evacuating the cylinder by drawing foul gases through exhaustports i5 as they are acted upon by the blast oi' air entering the ports24.

Manifestly, the construction as shown and described is capable of somemodification and such modification as .nay be construed to fall withinthe scope and meaning of the appended claims is also considered to bewithin the spirit and intent of the invention.

What is claimed is:

1. A fuel pump including a body having a valve controlled restrictionintermediate its ends, a plunger reciprocably arranged in said bodybelow said restriction having a valve controlled axial fuel passage, afuel supply line in communication with said body below said plunger, anactuating rod on said plunger, a cam adapted to axially move said rod,an oscillatabie, multi-toothed cam in juxtapositioned relation to saidfirst cam, and manually actuated means for oscillating saidmulti-toothed cam to vary the degree 0i' displacement of saidplunger-rod effected by said cam.

2. A fuel injector pump comprising a tubula body having a reciprocableplunger therein provided with an axial fuel passage, a Spring retainedvalve in said plunger, a spring retained valve in said body above saidplunger, a rotatable cam operative to reciprocate said plunger, anosciliatabie cam having a plurality of regularly spaced, peripheralteeth, and manually movable in relation to the void in said rotatable'cam to vary the degree of displacement of said plunger tocorrespondingly vary the volume of fuel passing through said injector.

3. In a fuel injector pump, a cylindrical body having an axial fuelpassage, a rotatable cam having a peripheral void, a plungerreciprocably disposed in the axial passage of said cylindrical body andactuated by said, cam, valvesin control of the fuel propelled by saidplunger, a toothed cam oscillatably mounted in juxtapositioned relationto said rotatable cam and manually controlled whereby its teeth will bemovably disposed in the void of said rotatable cam for controlling theeffect of the latter on said plunger to vary the volume of fuel pumpedthereby.

4. In a fuel injector pump, a tubular body, a plunger in said bodyhaving an axial fuel passage, valves in control of said passage, aplunger' rod, a rotatable cam for actuating said plunger rod toreciprocate said plunger, an oscillatable, multi-toothed cam adjacentsaid rotatable cam whose teeth are engageable with said rod atpredetermined positions of said cams for variably controlling thedisplacement of said plunger by said cam to correspondingly vary thequantity of fuel pumped by said plunger, and means for manuallyoperating said multi-toothed cam.

5. A fuel injector pump comprising a tubular body having a restrictionin its axial passage and a plunger reciprocably mounted therein belowsaid restriction', a spring retained valve in said plunger, a springretained valve in control of said restricted passage, a rotatable camfor reciprocating said plunger, and manually operated, multi-toothedcam, oscillatably disposed in juxtapositioned relationship with saidrotatable cam for increasing and decreasing the degree of displacementof said plunger as effected by said cam, and manual means for operatingsaid oscillatable cam.

6. A fuel pump comprising a tubular body having a reciprocable plungertherein, a camadapted to actuate said plunger, an oscillatable camhaving peripheral, regularly spaced teeth adjacent said cam forcontrolling the stroke of said plunger as effected bysaid cam, valvemeans in said tubular body to control the fuel propelled therethrough bysaid plunger and means for manually operating said oscillatable cam.

GARLIN E. SEALS.

REFERENCES CITED 5 The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 903,774 Remington Nov. 10, 1908903,902 Simmons Nov.'17, 1908 1,112,339 Teun Sept, 29, 1914 1,139,898Newcomb May 18, 1915 1,613,854 St. Clair Jan. 11, 1927 1,753,759 StalkerApr. 8,'1930 1,859,541 Thaheld May 24, 1932 1,917,791 Bellanca July 11,1933 1,929,885 Gosslau Oct. 10, 1933 1,938,271 Woolson Dec. 5, 19331,966,771 Thaheld July 17, 1934 2,162,683 Tobin June 13, 1939 FOREIGNPATENTS Number Country Date l 294,327 Great Britain 1928 362.749 GreatBritain 1931 688,991 France 1930 785,391 France 1935

